Randomised trial of acid inhibition by vonoprazan 10/20 mg once daily vs rabeprazole 10/20 mg twice daily in healthy Japanese volunteers (SAMURAI pH study)

Association of Physicians of India Consensus Recommendations for Vonoprazan in Management of Acid Peptic Disorders

The suppression of gastric acid secretion has long been the cornerstone of treatment for acid peptic disorders (APDs). Proton pump inhibitors (PPIs) have played a central role in managing these conditions, but their effectiveness can be hindered by notable limitations such as refractoriness or treatment failure due to inadequate acid suppression in some gastroesophageal reflux disease (GERD) patients, nonadherence to prescribed regimens due to the complexity of dosing, variability of response, and nocturnal acid breakthrough, etc. Vonoprazan is a first-in-class potassium-competitive acid blocker (P-CAB), recently introduced in India and also approved in several countries such as Japan, South Korea, and the USA. Extensive clinical evidence suggests that vonoprazan offers more potent acid suppression than PPIs. This consensus from the Association of Physicians of India (API) has been developed with the objective of providing key recommendations for the appropriate clinical usage of vonoprazan across various subsets of APDs, thereby optimizing the existing therapeutic options and improving the care and management of APD patients.

The efficacy and safety of Vonoprazan and Tegoprazan in Helicobacter pylori eradication: a comprehensive systematic review and meta-analysis of randomized controlled trials

Background

Potassium-competitive acid blocker (P-CAB)-based therapies are emerging as promising alternatives for eradicating Helicobacter pylori infection. However, the comparative efficacy of P-CAB-based therapy versus proton-pump inhibitor (PPI)-based therapy in treating H. pylori infection remains uncertain.

Objectives

This meta-analysis evaluated the efficacy and safety of P-CAB-based therapies, including Vonoprazan (VPZ) and Tegoprazan (TPZ), compared to PPI-based therapies for H. pylori infection. Subgroup analysis assessed the influence of drug history, experimental drug, treatment duration, combination therapies, and geographic regions on treatment outcomes.

Design

Meta-analysis.

Data sources and methods

Comprehensive searches were conducted in major databases, including PubMed, Embase, the Cochrane Library, and Web of Science, up to January 1, 2024. The primary outcome was the eradication rate, analyzed by intention-to-treat (ITT). Secondary outcomes included adverse events. Heterogeneity among studies was assessed using the χ2 test and the I 2 test. I 2 > 50% or p < 0.05 indicated significant heterogeneity.

Results

The analysis totally included 28 randomized controlled trials (RCTs) comprising 37 studies and 8818 patients diagnosed with H. pylori infection. Of these, 14 RCTs, including 20 studies and 4286 patients, compared P-CAB-based therapy with 14-day bismuth-based quadruple therapy (BQT). P-CAB-based therapy exhibited superior eradication rates compared to both 14-day BQT and PPI-based therapy (ITT analysis: 87.0% vs 79.8%, risk ratio (RR) = 1.08, 95% CI: 1.04-1.12, p < 0.0001; and 85.6% vs 77.8%, RR = 1.09, 95% CI: 1.05-1.12, p < 0.00001, respectively). This enhanced efficacy was particularly pronounced in patients with clarithromycin-resistant infections (73.7% vs 41.5%, RR = 1.53, 95% CI: 1.07-2.20, p = 0.02). Subgroup analysis demonstrated higher eradication rates with P-CAB-based therapy in treatment-naïve participants, VPZ recipients, and those receiving 7- or 14-day regimens (dual, triple, or quadruple therapy). However, no significant differences were observed in treatment-experienced subgroups, TPZ recipients, or those on 10-day regimens. In addition, P-CAB-based therapy showed a lower incidence of adverse events than PPI-based treatments (RR = 0.73, 95% CI: 0.63-0.86, p < 0.0001).

Conclusion

P-CAB-based therapies are more effective than traditional PPI-based treatments for eradicating H. pylori infection, with a reduced incidence of adverse events.

PROSPERO registration

CRD42024503665.

Vonoprazan Fumarate: A Promising Therapeutic Option for the Rapid Relief of Laryngopharyngeal Reflux Disease

OBJECTIVE

The aim is to examine the Reflux Symptom Score-12 (RSS-12) and assess the effectiveness of vonoprazan fumarate in managing laryngopharyngeal reflux disease (LPRD) among the Chinese population.

METHODS

A total of 140 patients with LPRD who were treated at our otorhinolaryngology outpatient clinic were included. The patients were randomly divided into the vonoprazan treatment group and the esomeprazole treatment group. The outcome indicators were the pretreatment and post treatment values of the Reflux Symptom Index (RSI), RSS-12, and reflux finding score.

RESULTS

The mean pretreatment RSS-12 and RSI values were 55.79 ± 11.94 and 18.67 ± 3.60 in the vonoprazan treatment group and 54.91 ± 11.95 and 18.44 ± 3.66 in the esomeprazole treatment group, respectively. Furthermore, both groups showed a significant decrease in the RSI and RSS-12 values after 4, 8, and 12 weeks of acid suppression therapy. In particular, 12 weeks of treatment led to a good treatment response in 91.4% and 87.1% of the patients in the vonoprazan treatment and esomeprazole treatment groups, respectively, based on their RSI values, and a favorable treatment response in 82.9% and 77.1% of those in the vonoprazan treatment and esomeprazole treatment groups, respectively, according to their RSS-12 values. More importantly, after 4 and 8 weeks of acid-suppressive therapy, the relative baseline change in RSS-12 scores in the vonoprazan treatment group was considerably larger than that in the omeprazole treatment group.

CONCLUSION

Compared to proton pump inhibitors (PPIs), vonoprazan fumarate has demonstrated superior early therapeutic efficacy, resulting in a notable improvement in laryngopharyngeal reflux symptoms at the start of treatment. When we extended acid-suppressive medication for 12 weeks, we saw a treatment effect comparable to that of PPIs.

Efficacy of Vonoprazan 10 mg and 20 mg for Patients With Proton Pump Inhibitor-Refractory Functional Dyspepsia: A Double-Blinded, Randomized Study

Background

A proportion of patients with functional dyspepsia (FD) have inadequate symptom control with proton pump inhibitors (PPIs) treatment. Vonoprazan demonstrates higher efficacy in acid reduction than PPI; however, the existing efficacy data for vonoprazan in treating PPI-refractory FD is limited.

Methods

This double-blinded, randomized controlled trial study was conducted at Rajavithi Hospital, Bangkok between December 2022 and 2023. Patients with FD who were unresponsive to the standard dose PPI were randomly assigned (1:1) to receive either 10 mg or 20 mg of vonoprazan for a 4-week duration, with a subsequent 4-week follow-up after treatment. The primary outcome was changes in the Global Overall Symptoms Scale (GOSS).

Results

Sixty patients were randomized without significant differences in baseline characteristics between both groups. The mean GOSS between the 10-mg vonoprazan and the 20-mg vonoprazan arm were 25.73 and 26.17 at week 0, 14.33 and 15.50 at week 2, 9.37 and 10.04 at week 4, and 9.79 and 9.33 at week 8, respectively (all p < 0.001 vs. baseline and p > 0.05 between groups). The quality of life was improved, with the Nepean dyspepsia index changing -4.13 and -4.25 at week 4, respectively (all p < 0.001 vs. baseline; p = 0.853 between groups). Symptom response rates (> 50% improvement in GOSS) were 72.4% and 75.9% at week 8, respectively (p = 0.24 between groups). No serious adverse events were observed.

Conclusion

Vonoprazan demonstrated significant effects in the alleviation of symptoms in PPI-refractory FD patients. There was no statistically significant difference in symptom alleviation between the 10 mg and 20 mg doses of vonoprazan.

Laryngopharyngeal Reflux Pathophysiology, Clinical Presentation, and Management: A Narrative Review

Laryngopharyngeal reflux (LPR) is a common and often misinterpreted clinical entity responsible for various symptoms affecting the upper aerodigestive tract. This narrative literature review aims to review the pathophysiology, symptoms, and management of LPR, emphasizing the emerging understanding of gastric content reflux in aerodigestive tissue irritation. Understanding the pathophysiology of LPR will allow general practitioners and specialists to accurately recognize and treat a condition that causes substantial morbidity in the affected patients. Using evidence-based findings from randomized controlled trials, clinical studies, and meta-analyses, the present investigation aims to outline and unify previous research into LPR. A review of anatomical structures, pathogenic mechanisms, endoscopic findings in LPR, and clinical manifestations and treatment options are also discussed. Though controversy around the diagnosis and management of LPR persists, emerging research in cellular damage and diagnostic tools promises to provide increasingly accurate and reliable modalities for characterizing LPR. Hopefully, future research will unify the field and provide overarching guidelines for both primary care and specialists. The present investigation provides an integrated perspective on LPR, a clinically prevalent and complex disease.

Vonoprazan-associated Clostridioides difficile infection: an analysis of the Japanese Adverse Drug Event Report and the FDA Adverse Event Reporting System

Background

Prolonged or excessive use of acid suppressants may increase the risk of Clostridioides difficile infection (CDI) by altering the intestinal microecosystem. Vonoprazan, a novel potassium-competitive acid blocker, exhibits a faster and more sustained acid-suppressive effect than proton pump inhibitors (PPIs). Therefore, vonoprazan may have a greater impact on the gut microbiota, potentially resulting in CDI.

Objectives

This study aimed to explore the potential relationship between acid suppressants and CDI by the Japan Adverse Drug Event Report (JADER) and the FDA Adverse Event Reporting System (FAERS) databases.

Design

A retrospective analysis of the JADER and FAERS databases was examined by disproportionality analysis.

Methods

We performed signal detection analyses of CDI induced by vonoprazan and PPIs using the JADER and FAERS databases. The association between acid suppressants and CDI was calculated using the reporting odds ratio (ROR) and corresponding 95% confidence interval (95% CI). When the lower limit of the 95% CI is exceeded by 1, the association is considered statistically significant.

Results

In the JADER database, the ROR (95% CI) for vonoprazan and PPIs based on suspect drug reports was 15.84 (12.23-20.50) and 2.51 (1.92-3.28), respectively. In the FAERS database, the ROR (95% CI) for vonoprazan and PPIs based on primary and secondary suspect drug reports was 11.50 (6.36-20.82) and 1.42 (1.34-1.51), respectively. Subgroup analysis showed that elderly patients aged 60 years and older were more strongly associated with CDI. The ROR (95% CI) for vonoprazan and PPIs in patients aged 60 years and older in the JADER database was 15.35 (11.59-20.33) and 1.65 (1.14-2.39), respectively. Similarly, the ROR (95% CI) for vonoprazan and PPIs in the FAERS database was 12.56 (6.26-25.20) and 1.43 (1.31-1.57), respectively. Excluding the effect of Helicobacter pylori (H. pylori) infection, the use of acid suppressants was still associated with CDI.

Conclusion

While signal detection analysis based on the JADER and FAERS databases could not establish causality, our study demonstrated that both vonoprazan and PPIs were significantly associated with CDI. Vonoprazan showed a stronger association with CDI in both databases.

Research on drug treatment and the novel signaling pathway of chronic atrophic gastritis

BACKGROUND

Chronic atrophic gastritis (CAG) is a global digestive system disease and one of the important causes of gastric cancer. The incidence of CAG has been increasing yearly worldwide.

PURPOSE

This article reviews the latest research on the common causes and future therapeutic targets of CAG as well as the pharmacological effects of corresponding clinical drugs. We provide a detailed theoretical basis for further research on possible methods for the treatment of CAG and reversal of the CAG process.

RESULTS

CAG often develops from chronic gastritis, and its main pathological manifestation is atrophy of the gastric mucosa, which can develop into gastric cancer. The drug treatment of CAG can be divided into agents that regulate gastric acid secretion, eradicate Helicobacter. pylori (H. pylori), protect gastric mucous membrane, or inhibit inflammatory factors according to their mechanism of action. Although there are limited specific drugs for the treatment of CAG, progress is being made in defining the pathogenesis and therapeutic targets of the disease. Growing evidence shows that NF-κB, PI3K/AKT, Wnt/ β-catenin, MAPK, Toll-like receptors (TLRs), Hedgehog, and VEGF signaling pathways play an important role in the development of CAG.

Evaluating vonoprazan and tegoprazan for gastroesophageal reflux disease treatment in Chinese Healthcare: an EVIDEM framework analysis

BACKGROUND

In Chinese healthcare settings, drug selection decisions are predominantly influenced by the Pharmacy & Therapeutics Committee (PTC). This study evaluates two recently introduced potassium-competitive acid blockers, vonoprazan (VPZ) and tegoprazan (TPZ), utilizing the Evidence and Value: Impact on DEcisionMaking (EVIDEM) framework.

METHODS

The study employed the 10th edition of EVIDEM, which includes a core model with five domains and 13 criteria. Two independent expert panels were involved: the PTC expert panel, tasked with assigning weights using a 5-point scale, defining scoring indicators, examining the evidence matrix, scoring, and decision-making; and the evidence matrix expert panel, responsible for conducting a systematic literature review, creating the evidence matrix, and evaluating the value contributions of VPZ and TPZ.

RESULTS

The analysis estimated the value contributions of VPZ and TPZ to be 0.59 and 0.54, respectively. The domain of 'economic consequences of intervention' showed the most significant variation in value contribution between the two drugs, followed by 'comparative outcomes of intervention' and 'type of benefit of intervention'.

CONCLUSION

Employing the EVIDEM framework, VPZ's value contribution was found to be marginally superior to that of TPZ. The EVIDEM framework demonstrates potential for broader application in Chinese medical institutions.

Vonoprazan causes symptomatic improvement in non-erosive gastroesophageal reflux disease: A systematic review and meta-analysis

OBJECTIVE

To evaluate the efficacy and safety of vonoprazan therapy as compared to conventional proton pump inhibitors (PPIs) or no vonoprazan for non-erosive esophagitis.

METHODS

A thorough search was conducted across databases. The primary outcome was to determine the mean variance in the gastroesophageal reflux disease (GERD) score after vonoprazan treatment. Secondary outcomes comprised alterations in the scores for epigastric pain and post-prandial distress, the proportion of patients displaying improvement, and the occurrence of adverse events. Pooled mean differences and relative risks were determined utilizing random effects models.

RESULTS

A total of 1,944 articles were screened and nine of them were included. As compared to PPI or no vonoprazan therapy, vonoprazan treatment led to a significant reduction in the GERD score [mean difference: -3.88 (95 % CI: -5.48, -2.28), p < 0.01, i2=95 %]. As compared to PPI or no vonoprazan therapy, vonoprazan treatment led to a significant reduction in the epigastric pain score [mean difference: -3.02 (95 % CI: -5.41, -0.63), p = 0.01, i2=75 %] and post-prandial distress score [mean difference: -2.82 (95 % CI: -3.51, -2.12), p < 0.01, i2=0 %] (all moderate GRADE evidence). Vonoprazan therapy was found to be safe.

CONCLUSION

Treatment with vonoprazan could significantly improve symptoms in patients with non-erosive esophagitis or non-erosive GERD.

Widespread use of proton pump inhibitors or potassium-competitive acid blocker has changed the status of gastrointestinal bleeding in patients with ischemic heart disease: real-world data from high volume centers

BACKGROUND

Although proton pump inhibitors (PPIs) or potassium-competitive acid blocker (PCAB) are useful in peptic ulcer prevention, their efficacy in preventing other gastrointestinal bleeding remains unclear. This study aimed to identify the status of gastrointestinal bleeding in the modern era when PPIs are widely used.

METHODS

This study included patients who underwent percutaneous coronary intervention (PCI) between 2018 and 2019 at two high-volume centers. Patients were categorized based on whether they experienced gastrointestinal bleeding within 2 years of PCI into groups A (patients who experienced gastrointestinal bleeding within 2 years after PCI) and B (patients who did not experience gastrointestinal bleeding).

RESULTS

Groups A and B included 21 (4.1%) and 494 (95.9%) patients, respectively (a total of 515 patients). Age at the initial PCI (77.8±2.4 and 72.0±0.5 years in groups A and B, respectively; p = 0.02), weight (53.8±3.2 and 61.8±0.7 kg in groups A and B, respectively; p = 0.01), and concomitant warfarin use (14.3% and 2.0% in groups A and B, respectively; p = 0.0005) were significantly different between the groups. The high bleeding risk rate (90.5% and 47.6% in groups A and B, respectively; p = 0.0001) was significantly different between the groups. A total of 95.9% of patients were taking PPIs or PCAB without significant differences between the groups. However, only one patient, who was taking steroids, had a gastric ulcer during PCAB treatment.

CONCLUSIONS

Acid-related upper gastrointestinal bleeding is largely controlled by PPIs in post-PCI patients. Furthermore, the risk factors for non-acid-related bleeding include older age, lower weight, and concomitant warfarin use.

The Time-Point Distribution Characteristics of Laryngopharyngeal Reflux in Elderly Patients

OBJECTIVE

To identify the characteristics of the time-point distribution of the occurrence of hypopharyngeal-proximal reflux episodes (HREs) in elderly and younger patients with laryngopharyngeal reflux (LPR).

STUDY DESIGN

Retrospective cohort study.

SETTING

Analysis of data from patients with LPR-related symptoms and 24-hour hypopharyngeal-esophageal multichannel intraluminal impedance-pH (24-hour HEMII-pH) monitoring from February 2017 to September 2022 at Sixth Medical Center of PLA General Hospital.

METHODS

Patients were divided into 2 age groups: the elderly group (>60 years) and the younger group (≤60 years). The time series of HREs and meals within 24 hours were analyzed based on HEMII-pH.

RESULTS

A total of 305 patients were included (126 elderly patients). In younger patients, except for nonacid-gas HREs, the incidence of the remaining types of HREs tended to increase within 2 hours after meals, especially after dinner. The incidence of all types of HREs pre- and postmeal was not significantly different in the elderly group (χ2  = 0.080, P = .777). The incidence of nighttime HREs in elderly patients was statistically higher than in younger patients (6.23% vs 3.96%, P = .030), particularly acid-/nonacid-liquid HREs.

CONCLUSION

HREs tend to increase within 2 hours after meals in younger LPR patients, except for nonacid-gas HREs. In elderly LPR patients, the incidence of all types of HREs pre- and postmeal were not significantly different, and nighttime fluid HREs was more prone to occur than in younger patients.

Potassium-competitive acid blockers: rethinking acid suppression for gastroesophageal reflux disease and Helicobacter pylori

Gastroesophageal reflux disease (GERD) and Helicobacter pylori (H. pylori) infection are different disease states that are united by the core role of acid suppression in their management. In GERD, proton pump inhibitors (PPIs) have long been standard therapy based on abundant positive clinical trial data supporting their efficacy and safety. In H. pylori, PPIs are also a critical element of therapy in combination with 1 or more antibiotics to achieve and maintain a pH that maximizes the efficacy of therapy. Despite the considerable clinical success and widespread use of PPIs, room remains for agents with differentiated pharmacokinetic and pharmacodynamic profiles. The potassium-competitive acid blockers (PCABs) are mechanistically distinct from PPIs but are acid-stable and do not require activation of the proton pump by coadministration of food. In pharmacodynamic studies, these agents have shown greater durations of acid suppression above the critical threshold of pH 4 (for GERD) and pH 6 (for H. pylori), which have been shown to optimize therapeutic efficacy in these settings. These results have translated in clinical studies to similar and, in some cases, improved outcomes relative to PPIs in these disease states. This review summarizes current knowledge on the physiology of acid secretion, pathophysiology and management of GERD and H. pylori, and key characteristics and clinical trial data for PPIs and PCABs.

Meta-analysis of Helicobacter pylori eradication therapy using vonoprazan as an acid suppressor compared with bismuth quadruple therapy

BACKGROUND

Vonoprazan, a novel acid suppressant, has recently emerged as a regimen for eradicating Helicobacter pylori. However, uncertainties exist about the effectiveness and safety of VPZ-based regimens compared with those of bismuth-based quadruple therapy in eradicating H. pylori. The present meta-analysis was performed to compare the effectiveness and safety of vonoprazan-based regimens with those of bismuth quadruple therapy in eradicating H. pylori.

MATERIALS AND METHODS

All randomized controlled trials and non-randomized controlled trials comparing the vonoprazan-based therapy with the bismuth quadruple therapy were included in this meta-analysis. Information was also extracted by two evaluators, and if heterogeneity existed, a random-effects model was used to calculate the combined relative ratio and 95% confidence interval; otherwise, a fixed-effects model was used. And subgroup analyses were performed to explore the sources of heterogeneity.

RESULTS

A total of 10 studies, comprising 2587 patients were included in the meta-analysis. The results showed that the combined eradication rate of patients treated with the vonoprazan-based regimen was significantly higher than that of patients treated with bismuth quadruple therapy, in both intention-to-treat and per-protocol analyses, and the differences were statistically significant. Among the intention-to-treat analyses results: (90.28% vs. 83.64% [odds ratio (OR) = 1.85, 95% confidence interval (CI) (1.27, 2.70), p = 0.001]); in the per-protocol analyses: (94.80% vs. 89.88%, [OR = 2.25, 95% CI (1.37, 3.69), p = 0.001]). The occurrence of adverse events was significantly lower in patients treated with vonoprazan-based regimens than in those treated with bismuth quadruple therapy, (14.50% vs. 25.89%, [OR = 0.49, 95% CI (0.32, 0.75), p = 0.001]).

CONCLUSIONS

For eradicating H. pylori, vonoprazan-based regimens are remarkably advantageous over bismuth quadruple therapy. Furthermore, vonoprazan-based regimens exhibit a lower rate of adverse events than bismuth quadruple therapy.

Evolving Concepts in Helicobacter pylori Management

Helicobacter pylori is the most common chronic bacterial infection worldwide and the most significant risk factor for gastric cancer, which remains a leading cause of cancer-related death globally. H pylori and gastric cancer continue to disproportionately impact racial and ethnic minority and immigrant groups in the United States. The approach to H pylori case-finding thus far has relied on opportunistic testing based on symptoms or high-risk indicators, such as racial or ethnic background and family history. However, this approach misses a substantial proportion of individuals infected with H pylori who remain at risk for gastric cancer because most infections remain clinically silent. Moreover, individuals with chronic H pylori infection are at risk for gastric preneoplastic lesions, which are also asymptomatic and only reliably diagnosed using endoscopy and biopsy. Thus, to make a significant impact in gastric cancer prevention, a systematic approach is needed to better identify individuals at highest risk of both H pylori infection and its complications, including gastric preneoplasia and cancer. The approach to H pylori eradication must also be optimized given sharply decreasing rates of successful eradication with commonly used therapies and increasing antimicrobial resistance. With growing acceptance that H pylori should be managed as an infectious disease and the increasing availability of susceptibility testing, we now have the momentum to abandon empirical therapies demonstrated to have inadequate eradication rates. Molecular-based susceptibility profiling facilitates selection of a personalized eradication regimen without necessitating an invasive procedure. An improved approach to H pylori eradication coupled with population-level programs for screening and treatment could be an effective and efficient strategy to prevent gastric cancer, especially in minority and potentially marginalized populations that bear the heaviest burden of H pylori infection and its complications.

Keverprazan, a novel potassium-competitive acid blocker: Single ascending dose safety, tolerability, pharmacokinetics, pharmacodynamics and food effect in healthy subjects

BACKGROUND

Keverprazan is a novel potassium-competitive acid blocker for the treatment of acid-related diseases.

AIMS

To evaluate the safety, pharmacokinetics, pharmacodynamics, and food effect of single oral doses of keverprazan in healthy Chinese subjects.

METHODS

In the dose-escalated phase Ia trial, the first 8 subjects received keverprazan 5 mg, the others successively entered 10 mg, 20 mg, 40 mg, 60 mg groups and were randomized to receive keverprazan (n = 8), lansoprazole (LSZ) 30 mg (n = 2) or placebo (n = 2) in each dose group. The phase Ib study randomly enrolled subjects to the fasting-fed (n = 7) or fed-fasting (n = 7) groups for evaluating the food effect of keverprazan.

RESULTS

Twenty (35.71%) adverse events (AEs) occurred in phase Ia, including 13 (32.50%), 3 (37.50%), and 4 (50.00%) AEs in the keverprazan, placebo, and LSZ groups, respectively. Four (28.57%) AEs occurred in Phase Ib. The Tmax of keverprazan was 1.25-1.75 h. Cmax and AUC increased with the dose, and the t1/2, CL/F were 6.00-7.17 h, 88.8-198 L/h, respectively. The intragastric pH >5 holding-time ratio (HTR) increased with the dose but reached a ceiling at 20 mg. In the 30 mg LSZ and 5-60 mg keverprazan groups, the intragastric pH >5 HTRs during 24 h were 57.1%±26.4%, 7.9%±8.1%, 26.2%±22.8%, 80.2%±8.8%, 88.1%±8.6%, and 93.0%±1.7%, respectively. The geometric mean ratios (90% CI) of Cmax and AUC0-∞ of keverprazan in plasma under the fed vs. fasting state were 126.8% (109.0%-147.5%) and 134.9% (123.8%-146.9%).

CONCLUSION

Keverprazan is tolerable, and provides significant stable and lasting inhibition efficacy of intragastric acidity at 20 mg.

Efficacy of Tegoprazan in Patients with Laryngopharyngeal Reflux Disease: A Preliminary Feasibility Study

Tegoprazan is a novel, potent, and highly selective potassium-competitive acid blocker that inhibits gastric acid secretion with rapid onset of action and prolonged control of gastric acidity. We performed a preliminary feasibility study to evaluate whether tegoprazan could control symptoms more effectively than a placebo in patients with laryngopharyngeal reflux disease (LPRD). In this double-blind, randomized, placebo-controlled trial, 35 patients with LPRD were randomly assigned to two groups: tegoprazan 50 mg daily and placebo. The primary endpoint was the complete resolution rate of LPRD symptoms after 8 weeks of medication, and the secondary endpoints were the complete resolution rate of LPRD symptoms after 4 weeks of medication and changes in the reflux symptom index (RSI) and reflux finding score (RFS) from baseline at 4 and 8 weeks of medication. There was no difference in the complete symptom resolution rates at 8 weeks between the tegoprazan and placebo groups (29.4% [5/17] vs. 27.8% [5/18], p = 1.000). Moreover, there was no significant difference in the complete symptom resolution rates at 4 weeks between the two groups. Compared with the baseline, both tegoprazan and placebo significantly reduced the total RSI and RFS scores after 4 and 8 weeks of medication; however, tegoprazan was not superior to the placebo. In conclusion, tegoprazan (50 mg daily) administration improved LPRD symptoms and signs. However, tegoprazan did not show superiority over placebo. Considering the potential effectiveness of tegoprazan as an acid-suppressing therapy and the possibility of type II error due to a low number of included patients herein, prospective, large-scale, multi-center studies with a higher dose of tegoprazan for a prolonged duration are required to elucidate the efficacy of tegoprazan in patients with LPRD. (ClinicalTrials.gov: NCT05871398).

Efficacy and safety of vonoprazan-amoxicillin dual therapy for Helicobacter pylori first-line treatment: a single-center, randomized, controlled trial

Background

With the increase in antibiotic resistance, the success rate of Helicobacter pylori (H. pylori) eradication therapy has declined in recent years. Vonoprazan-amoxicillin (VA) dual therapy has been reported to be a promising regimen.

Objectives

To compare the efficacy and safety of VA dual therapy and bismuth quadruple therapy containing amoxicillin and clarithromycin for H. pylori first-line eradication, and to further analyze the effects of clarithromycin resistance on eradication rate.

Design

This study was a single-center, open-label, randomized controlled trial.

Methods

Treatment-naïve H. pylori-infected patients were randomly allocated 1:1 to the VA group (vonoprazan 20 mg twice daily and amoxicillin 750 mg four times daily, for 14 days) or the RBAC group (rabeprazole 10 mg, bismuth potassium citrate 220 mg, amoxicillin 1000 mg and clarithromycin 500 mg twice daily, for 14 days). H. pylori clarithromycin resistance and CYP2C19 gene polymorphisms were detected with real-time polymerase chain reaction (PCR) technique. The eradication rates and adverse events were analyzed.

Results

A total of 151 patients were enrolled. The intention-to-treat (ITT), modified intention-to-treat (mITT), and per-protocol (PP) eradication rates and their 95% confidence intervals (95% CIs) were 94.6% (86.0-98.3%), 98.6% (91.3-99.9%), and 98.5% (90.9-99.9%) for VA group and 87.0% (77.0-93.3%), 91.8% (82.3-96.6%), and 93% (83.7-97.4%) for RBAC group. The eradication rate of the VA group was noninferior to the RBAC group in ITT, mITT, and PP analyses (p < 0.0001). In patients infected with strains of clarithromycin resistance point mutation, the eradication rate of the RBAC group decreased to lower than 90%, but the difference from the VA group did not achieve statistical significance (ITT eradication rate: 81.5% in the RBAC group and 96.2% in the VA group, p = 0.192). The incidence of adverse events in the VA group was 39.2%, which was significantly lower than that in the RBAC group (79.2%, p = 0.000).

Conclusion

The efficacy of VA dual therapy is noninferior to RBAC in H. pylori first-line eradication, with fewer adverse reactions.

Registration

This study was registered at the Chinese Clinical Trial Registry (ChiCTR2100052550) on 30 October 2021.

A Modified 14-Day Dual Therapy with Vonoprazan and Amoxicillin Amplified the Advantages Over Conventional Therapies for Eradication of Helicobacter pylori: A Non-Inferiority Clinical Trial

Purpose

The emergence of resistant strains has greatly reduced the eradication rate of H. pylori (HP) in conventional bismuth-containing quadruple therapy. Meanwhile, the new 7-day dual therapy with vonoprazan (VPZ) and amoxicillin (AMO) failed to achieve the expected therapeutic effect in China.

Patients and Methods

A total of 256 untreated HP-infected patients are included in this non-inferiority clinical trial. The patients were randomly divided into three groups: 14-day dual therapy group (VPZ 20mg b.i.d + AMO 750mg t.i.d for 14 days, VA14), 14-day modified triple therapy group (VA14 + Jinghua Weikang Capsule 160mg t.i.d, VAC), and conventional bismuth-containing quadruple therapy group for 14 days (BCQ). Eradication rates, drug-related adverse events (AEs), patient compliance, and drug costs were compared among the three groups.

Results

The eradication rates in the BCQ, VA14, and VAC were 78.67, 77.33%, and 86.49% by intention-to-treat analysis, respectively, and 96.72%, 90.63%, and 92.75% by pre-protocol or modified intention-to-treat analysis, respectively. VA14 therapy indicated a non-inferiority eradication rate and advanced safety and economics to BCQ therapy. JWC further improved the eradication rate and reduced the incidence of AEs.

Conclusion

A modified 14-day dual therapy with VPZ and AMO provides satisfied efficacy as the first-line treatment for HP infection in China.

Frontiers in Endoscopic Treatment for Gastroesophageal Reflux Disease

BACKGROUND

The 3rd edition of the evidence-based clinical practice guidelines for gastroesophageal reflux disease (GERD) 2021 from the Japanese Society of Gastroenterology states that the treatment strategy for potassium-competitive acid blocker (PCAB)-refractory GERD remains unclear. Furthermore, even if GERD improves with the administration of an acid secretion inhibitor, it is feared that GERD may flare up after discontinuation of the drug, resulting in some cases in which patients are forced to take vonoprazan semipermanently (the so-called PCAB-dependent cases). From a global perspective, PCAB is not yet used in all countries and regions, and measures that can be taken now for cases in which a conventional proton pump inhibitor (PPI) is inadequately effective need to be devised.

SUMMARY

Endoscopic treatment for GERD may be effective in cases where conventional proton pump inhibitors are ineffective; however, there are insufficient long-term studies to corroborate this, and its cost effectiveness is unknown. Other treatment options for PCAB or PPI-refractory GERD include surgical procedures (Nissen and Toupet operations), which have a longer history than endoscopic treatment for GERD. However, their long-term results are not as good as those of acid secretion inhibitors, and they are not cost effective. Endoscopic treatment for GERD may fill gaps in inadequate surgical treatment. In April 2022, endoscopic anti-reflux mucosal resections (ARMS [anti-reflux mucosectomy] and ESD-G [endoscopic submucosal dissection for GERD]) were approved for reimbursement, making endoscopic treatment of GERD possible throughout Japan.

KEY MESSAGES

It is important to identify the background factors in cases in which endoscopic treatments are effective.

Current Treatment of Laryngopharyngeal Reflux

Objectives: Laryngopharyngeal reflux (LPR) is a complex syndrome characterized by the reflux of gastroduodenal contents into the pharynx or larynx, resulting in a range of symptoms, including chronic cough, throat clearing, pain, dysphagia, hoarseness, and dysphonia. Despite the lack of a gold standard for diagnosis or treatment, various strategies have been proposed to manage LPR. However, the effectiveness of these treatments is compromised by the lack of a uniform treatment protocol, which places a burden on patients, physicians, and the healthcare system. This study aims to systematically review the treatments of LPR and provide updated and useful clinical information to clinical physicians. Methods: The literature with an emphasis on LPR and related keywords is searched and reviewed in PubMed. Results: Treatment of LPR includes health education, lifestyle modification, dietary changes, medications, and surgery, as well as the emergence of a novel treatment method involving external upper esophageal sphincter compression devices. Conclusions: Currently, medication is the main treatment, supplemented with lifestyle and dietary changes, but there is still a lack of effective means for patients with drug-resistant or intolerant LPR. More high-quality and rigorous trials must continue to be conducted to determine the best treatment options and find novel treatments. Taking into account the complexity of LPR, this study proposes a simple algorithm to help clinicians with the initial management of this disease.

Cost-Effectiveness of Vonoprazan-Based and Rifabutin-Based vs Other Regimens as First-Line Treatment of Helicobacter pylori Infection in the United States

INTRODUCTION

The economic and clinical implications of eradicating Helicobacter pylori ( H. pylori ) with vonoprazan-based and rifabutin-based regimens vs other existing prepackaged first-line treatment options in the United States are unknown. Therefore, we evaluated the cost-effectiveness of vonoprazan-based and rifabutin-based and other prepackaged regimens for the first-line treatment of H. pylori from the perspective of US healthcare payers.

METHODS

We used the state-transition Markov model to conduct a cost-effectiveness analysis of H. pylori eradication with clarithromycin triple, bismuth quadruple, vonoprazan dual, vonoprazan triple, and rifabutin triple regimens. In a cycle length of 2 months, the model estimated the expected costs (expressed in 2022 US$), expected quality-adjusted life-years (QALY), incremental cost-effectiveness ratios, and expected net monetary benefit over 20 years. In addition, we accounted for the present value of future costs and QALY by applying a 3% discounting rate.

RESULTS

In this study, rifabutin triple therapy had a lower expected cost but was more effective than clarithromycin triple, bismuth quadruple, and vonoprazan dual regimens; hence, it dominated them. Vonoprazan triple therapy had a higher expected cost (US$ 1,172 vs US$ 1,048) and expected QALY (14.262 vs 14.256) than rifabutin triple therapy, yielding an estimated incremental cost-effectiveness ratio of US$ 22,573/QALY. The study suggested that vonoprazan triple treatment had the highest expected net monetary benefit and was the most cost-effective at willingness-to-pay thresholds between US$50,000 and US$150,000 per QALY, followed by rifabutin triple therapy.

DISCUSSION

H. pylori infection eradication with vonoprazan triple therapy would provide the greatest net health and monetary benefit from the perspective of US healthcare payers.

Vonoprazan poses no additional risk of developing Clostridioides difficile infection compared to proton pump inhibitors

BACKGROUND AND AIM

The use of proton pump inhibitors (PPIs) has been repeatedly reported as a trigger of Clostridioides difficile infection (CDI), a leading cause of nosocomial diarrhea. However, only a few studies have reported on the association between vonoprazan, a novel potassium-competitive acid blocker providing potent acid suppression, and CDI, with no studies having been conducted in a clinical setting. We therefore evaluated the association between various classes of acid suppressants and CDI with special attention paid to differences in the magnitudes of association between PPIs and vonoprazan.

METHODS

A retrospective hospital-based cohort from a secondary-care hospital in Japan (n = 25 821) was collected, wherein eligible CDI cases were defined as hospital-onset cases (n = 91). A multivariable adjusted logistic regression analysis for the entire cohort and propensity analyses for subgroups consisting of PPI and/or vonoprazan users at various doses (n = 10 306) were performed.

RESULTS

The overall CDI incidence rate was 1.42/10 000 patient-days, which was comparable with previous reports. A multivariable analysis showed that both PPIs and vonoprazan were positively associated with CDI (odds ratios [95% confidence intervals]: 3.15 [1.67-5.96] and 2.63 [1.01-6.88], respectively). In addition, matched subgroup analyses showed that PPIs and vonoprazan had equivalent magnitudes of association with CDI.

CONCLUSIONS

We found that both PPIs and vonoprazan were associated with CDI, and the magnitude of the association was comparable. Because vonoprazan is widely available in Asian countries, further studies on the association of its usage with CDI are warranted.

Pharmacological Treatment of Functional Dyspepsia: An Old Story Revisited or a New Story to Be Told? A Clinical Review

Dyspepsia incorporates a set of symptoms originating from the gastroduodenal region, frequently encountered in the adult population in the Western world. Most patients with symptoms compatible with dyspepsia eventually end up, in the absence of a potential organic cause, being diagnosed with functional dyspepsia. Many have been the new insights in the pathophysiology behind functional dyspeptic symptoms, namely, hypersensitivity to acid, duodenal eosinophilia, and altered gastric emptying, among others. Since these discoveries, new therapies have been proposed. Even so, an established mechanism for functional dyspepsia is not yet a reality, which makes its treatment a clinical challenge. In this paper, we review some of the possible approaches to treatment, both well established and some new therapeutic targets. Recommendations about dose and time of use are also made.

Re-bleeding and all-cause mortality risk in non-variceal upper gastrointestinal bleeding: focusing on patients receiving oral anticoagulant therapy

OBJECTIVE

Non-variceal upper gastrointestinal bleeding (NVUGIB) in patients receiving oral anticoagulants (OACs) may be fatal; however, little is known about re-bleeding and all-cause mortality after successful hemostasis. We investigated the clinical characteristics and risk factors for re-bleeding and death after successful hemostasis.

METHODS

Patients receiving OACs and diagnosed with NVUGIB between 2007 and 2021 were enrolled. All NVUGIB incidents were confirmed if definite bleeding in the upper gastrointestinal tract was detected via esophagogastroduodenoscopy.

RESULTS

A total of 132 patients receiving OACs were diagnosed with NVUGIB. Males were the majority (72, 54.5%), and bleeding was detected mostly in the stomach (99, 75%) and was most often due to peptic ulcers (PU) (88, 66.7%). After successful hemostasis of index NVUGIB, 40 patients (30.3%) experienced re-bleeding. Among them, 15 (37.5%) died, and among those, 3 (2.3%) were related to re-bleeding. Multivariate analysis revealed that duodenal bleeding (odds ratio [OR]: 3.305; 95% confidence interval [CI]: 1.152-9.479, p = 0.026) and Charlson comorbidity index score (CCI) (OR: 1.22; 95% CI: 1.052-1.419, p = 0.009) were significant risk factors for re-bleeding. Index albumin levels (OR: 0.134; 95% CI: 0.035-0.506, p = 0.003), previous PU or upper gastrointestinal bleeding (UGIB) history (OR: 4.626; 95% CI: 1.375-15.567, p = 0.013), and CCI (OR: 1.293; 95% CI: 1.058-1.581, p = 0.012) were related all-cause mortality.

CONCLUSION

CCI and duodenal bleeding are risk factors for re-bleeding in patients with NVUGIB who were receiving OACs, while low index albumin levels and previous PU and UGIB history are associated with all-cause mortality.

The role of vonoprazan in patients with erosive esophagitis

Acid suppression is the primary therapy for erosive esophagitis (EE). Although proton pump inhibitors (PPIs) are considered as the first-line medication for EE, 10-20% of patients with Los Angeles C and D grade EE do not gain complete mucosal healing and symptom control despite 8-week double-dose PPI treatment. Vonoprazan is a novel potassium-competitive acid blocker (P-CAB), which blocks the H+, K+-adenosine triphosphatase enzymes in a K+-competitive and reversible manner. Vonoprazan exhibits different pharmacological and pharmacokinetic profiles from conventional PPIs, and has a rapid, potent and sustained acid inhibitory effect. In this review, we summarized and discussed current evidence regarding the role of vonoprazan in terms of mucosal healing, maintaining remission and symptom relief for the management of EE, including the initial and maintenance treatment of EE, as well as for PPI-resistant EE patients. Safety concerns and cost-effectiveness analysis of vonoprazan were also mentioned in the article. As a potent and well-tolerated acid blocker, vonoprazan has the potential to become a novel option for the management of EE.

Vonoprazan Triple and Dual Therapy for Helicobacter pylori Infection in the United States and Europe: Randomized Clinical Trial

BACKGROUND & AIMS

Novel, effective treatments for Helicobacter pylori infection are needed. This study evaluated the efficacy of vonoprazan, a potassium-competitive acid blocker, vs standard treatment on H pylori eradication in the United States and Europe.

METHODS

In a randomized, controlled, phase 3 trial, treatment-naïve adults with H pylori infection were randomized 1:1:1 to open-label vonoprazan dual therapy (20 mg vonoprazan twice daily; 1 g amoxicillin 3 times daily), or double-blind triple therapy twice a day (vonoprazan 20 mg or lansoprazole 30 mg; amoxicillin 1 g; clarithromycin 500 mg) for 14 days. The primary outcome was noninferiority in eradication rates in patients without clarithromycin- and amoxicillin-resistant strains (noninferiority margin = 10%). Secondary outcomes assessed superiority in eradication rates in clarithromycin-resistant infections, and in all patients.

RESULTS

A total of 1046 patients were randomized. Primary outcome eradication rates (nonresistant strains): vonoprazan triple therapy 84.7%, dual therapy 78.5%, vs lansoprazole triple therapy 78.8% (both noninferior; difference 5.9%; 95% confidence interval [CI], -0.8 to 12.6; P < .001; difference -0.3%; 95% CI, -7.4 to 6.8; P = .007, respectively). Eradication rates in clarithromycin-resistant infections: vonoprazan triple therapy 65.8%, dual therapy 69.6%, vs lansoprazole triple therapy 31.9% (both superior; difference 33.9%; 95% CI, 17.7-48.1; P < .001; difference 37.7%; 95% CI, 20.5-52.6; P < .001, respectively). In all patients, vonoprazan triple and dual therapy were superior to lansoprazole triple therapy (80.8% and 77.2%, respectively, vs 68.5%, difference 12.3%; 95% CI, 5.7-18.8; P < .001; difference 8.7%; 95% CI, 1.9-15.4; P = .013). Overall frequency of treatment-emergent adverse events was similar between vonoprazan and lansoprazole regimens (P > .05).

CONCLUSION

Both vonoprazan-based regimens were superior to proton pump inhibitor-based triple therapy in clarithromycin-resistant strains and in the overall study population.

CLINICALTRIALS

gov; NCT04167670.

Influence of daily versus alternate-day dosing of vonoprazan on intragastric pH, serum gastrin, and the antiplatelet function of clopidogrel : Influence of alternate-day dosing of vonoprazan

BACKGROUND

Vonoprazan, a potassium-competitive acid blocker, inhibits gastric acid secretion and attenuates the antiplatelet function of clopidogrel more potently than esomeprazole. We investigated whether alternate-day dosing of vonoprazan might avoid this interaction with clopidogrel while providing sufficient gastric acid inhibition.

METHODS

Following 24 h of pH monitoring (control regimen), 12 healthy volunteers received three regimens (clopidogrel-only regimen: clopidogrel 75 mg daily [q.d.]; vonoprazan alternate-day regimen: vonoprazan 10 mg every other day [q.o.d.] + clopidogrel 75 mg q.d.; vonoprazan daily regimen: vonoprazan 10 mg q.d. + clopidogrel 75 mg q.d.) for 14 days in a randomized open-label crossover manner. Intragastric pH monitoring was performed for 24 h on day 13 in the clopidogrel-only and vonoprazan q.d. regimens and for 48 h on days 13 and 14 in the vonoprazan q.o.d. regimen. Serum gastrin and inhibition of platelet aggregation (IPA) were measured before the commencement of pH monitoring in each regimen.

RESULTS

Twelve volunteers completed the study. Equivalent median IPA values in the q.o.d. and q.d. regimens were measured (21.8% and 25%, respectively) and were significantly lower than that with the clopidogrel-only regimen (40.8%). The median pH4 holding time ratio for the vonoprazan q.o.d. regimen (49.7%) was superior to that of the clopidogrel-only regimen (18.4%), but was significantly inferior to that of the vonoprazan q.d. regimen (77.0%; p < 0.01).

CONCLUSION

Alternate-day administration of vonoprazan could not prevent the interaction between vonoprazan and clopidogrel, and acid inhibition was inferior to that with vonoprazan daily administration. Alternate-day administration of vonoprazan thus appears to be of questionable clinical utility.

Effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases: physiopathology and therapeutic targets

PURPOSE

Laryngopharyngeal reflux disease (LPRD) is a general term for the reflux of gastroduodenal contents into the laryngopharynx, oropharynx and even the nasopharynx, causing a series of symptoms and signs. Currently, little is known regarding the physiopathology of LPRD, and proton pump inhibitors (PPIs) are the drugs of choice for treatment. Although acid reflux plays a critical role in LPRD, PPIs fail to relieve symptoms in up to 40% of patients with LPRD. The influence of other reflux substances on LPRD, including pepsin, bile acid, and trypsin, has received increasing attention. Clarification of the substances involved in LPRD is the basis for LPRD treatment.

METHODS

A review of the effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases was conducted in PubMed.

RESULTS

Different reflux substances have different effects on LPRD, which will cause various symptoms, inflammatory diseases and neoplastic diseases of the laryngopharynx. For LPRD caused by different reflux substances, 24-h multichannel intraluminal impedance combined with pH-metry (MII-pH), salivary pepsin, bile acid and other tests should be established so that different drugs and treatment courses can be used to provide patients with more personalized treatment plans.

CONCLUSION

This article summarizes the research progress of different reflux substances on the pathogenesis, detection index and treatment of LPRD and lays a theoretical foundation to develop target drugs and clinical diagnosis and treatment.

Outcomes of endoscopic submucosal dissection for gastroesophageal reflux disease (ESD-G) for medication-refractory gastroesophageal reflux disease: 35 cases underwent ESD-G including 15 cases followed more than 5 years

Background

Although some kinds of endoluminal surgery for patients with proton pump inhibitor (PPI)-refractory gastroesophageal reflux disease (GERD) have been reported, there are few reports on their long-term outcomes. In 2014, we reported the effectiveness of endoscopic surgery for PPI-refractory GERD, which we invented and named endoscopic submucosal dissection for GERD (ESD-G) in 2008. Thereafter, we accumulated more cases and monitored the patients’ condition postoperatively and describe the outcomes herein.

Patients and methods

This single-center, single-arm trial was conducted at the Osaka Medical and Pharmaceutical University Hospital. We compared outcomes between before and 3–6 months after ESD-G. Additionally, we investigated the outcomes of patients 5 or more years after ESD-G.

Results

We performed 42 ESD-G procedures in 35 patients between 2008 and 2020. In seven patients, ESD-G was performed twice for various reasons. The frequency scale for the symptoms of GERD score was significantly improved 3–6 months after ESD-G (22 → 10, p < 0.0001); the Los Angeles classification for reflux esophagitis was clearly improved after ESD-G (p = 0.0423). The number of reflux episodes was not decreased by ESD-G. There was a significant difference in the potency unit of gastric acid secretion suppressants for controlling GERD-related symptoms between baseline and 3–6 months after ESD-G (p = 0.0009). In patients without a history of distal gastrectomy who underwent ESD-G, the potency unit of gastric acid secretion suppressants significantly decreased 5 or more years after ESD-G (p = 0.0121).

Conclusion

ESD-G may be effective in patients with refractory GERD-related symptoms without a history of distal gastrectomy.

The Effect of Food on the Pharmacokinetics of the Potassium-Competitive Acid Blocker Vonoprazan

Herein, we report a food‐effect study of vonoprazan, an oral potassium‐competitive acid blocker. In a phase 1, randomized, open‐label, crossover study, healthy subjects received a single 20‐mg dose of vonoprazan either following an overnight fast or 30 minutes after a high‐fat breakfast. Plasma vonoprazan levels were determined at 0 hour and at 17 subsequent assessment points up to 48 hours after dosing. After a 5‐day washout, subjects received a second 20‐mg vonoprazan dose in the alternative fed/fasted state (identical process repeated). Twenty‐four subjects completed the study. Vonoprazan exposure was not meaningfully affected by food. Geometric mean ratios for maximum concentration, area under the concentration‐time curve from time 0 to 24 hours, and area under the plasma concentration–time curve extrapolated to infinity obtained under fed and fasting conditions were 1.05 (90% confidence interval, 0.98‐1.12), 1.13 (1.09‐1.18), and 1.15 (1.11‐1.19), respectively. Four subjects experienced 6 adverse events that were all mild and considered unrelated to the study drug. Vonoprazan can be administered without regard to food intake.

Potent Acid Suppression With Vonoprazan vs Proton Pump Inhibitors Does Not Have Higher Association With Clostridioides difficile Infection

INTRODUCTION

Proton pump inhibitors (PPIs) are associated with the onset of Clostridioides difficile infection (CDI). Although a new potassium-competitive acid blocker, vonoprazan, consistently shows a more potent acid inhibitory effect in comparison to PPIs, the risk of CDI in vonoprazan-treated patients relative to those treated with PPIs is unknown. In this retrospective case-control study, using a nationwide hospital-based administrative database in Japan, we investigated the association of the onset of CDI in patients treated with vonoprazan.

METHODS

A CDI case was defined as a case in which a patient was diagnosed and treated for CDI. For each CDI case, 3 non-CDI patients were extracted as controls. Information on the usage of acid suppressants in the 2 months before the onset of CDI and other confounding factors was collected. Relative associations of gastric acid suppressants with the onset of CDI were estimated.

RESULTS

A total of 4,466 CDI cases and 13,220 of non-CDI controls were extracted. A multivariate conditional regression analysis revealed that PPI or vonoprazan use was modestly, but significantly associated with CDI (odds ratio [95% confidence interval]: PPI, 1.3 [1.2-1.4]; vonoprazan, 1.4 [1.2-1.7]). With PPI users as a reference, vonoprazan did not show a stronger association with CDI (odds ratio [95% confidence interval]: 1.07 [0.91-1.26]).

DISCUSSION

We found a significant positive association between vonoprazan use and CDI; however, the magnitude of the association was not beyond that in PPI users. This is the first report on any potential adverse effects of vonoprazan.

Administration of a standard dose of vonoprazan fumarate delays gastric emptying in Japanese healthy adults: a prospective clinical trial

BACKGROUND

There is no established view of how gastric acid suppression affects the time for gastric emptying. Vonoprazan fumarate shows potent and durable gastric acid inhibitory effects, but its effects on gastric emptying have not been studied widely. We investigated the effects of vonoprazan fumarate on gastric emptying and measured serum gastrin and plasma ghrelin levels in healthy adults.

METHODS

Ten participants were administered 10 mg vonoprazan fumarate daily for 14 days, then 20 mg vonoprazan fumarate daily for 14 days. The gastric emptying breath test was performed and serum gastrin levels were measured at baseline and after each medication administration period. The protocol was then repeated, with the gastric emptying breath test and serum gastrin and plasma desacyl-ghrelin levels measured at baseline and the end of the medication trial.

RESULTS

Mean serum gastrin levels increased in a dose-dependent manner [baseline: 104.7 ± 50.4, after 10 mg protocol: 328 ± 123.8, after 20 mg protocol: 555 ± 378.8 (pg/mL, mean ± standard deviation), p = 0.0008]. There was a significant difference between the gastric emptying breath test Tmax at baseline and just after the 20 mg protocol (baseline: 45.5 ± 15.3, after 20 mg protocol: 60.5 ± 19.6 min, p = 0.0418). Plasma desacyl-ghrelin levels increased significantly just after the 20 mg protocol compared to those at baseline [baseline: 222.3 ± 106.4, after 20 mg protocol: 366.2 ± 178.6 (fmol/mL), p = 0.0008].

CONCLUSIONS

In healthy adults, 14 days of vonoprazan fumarate administration at 20 mg/day delayed gastric emptying.

TRIAL REGISTRATION

This clinical trial was registered in the University hospital Medical Information Network Clinical Trial Registry (Trial No. UMIN000039199 and UMIN000042969).

Effects of pirenzepine on vonoprazan-induced gastric acid inhibition and hypergastrinemia

BACKGROUND

Compared to proton pump inhibitors, vonoprazan exerts a greater inhibitory effect on gastric acid secretion and is useful for treating acid-related diseases, such as gastro-esophageal reflux disease. However, there is a problem that vonoprazan causes hypergastrinemia, which confers a risk of carcinoid tumor. A previous report demonstrated that pirenzepine, an M1 muscarinic receptor antagonist, enhances the acid inhibitory effects while suppressing hypergastrinemia induced by omeprazole. Here, we examined whether pirenzepine enhances the gastric acid inhibitory effects of vonoprazan without further increasing serum gastrin levels.

METHODS

Eleven healthy volunteers were subjected to 24-h intragastric pH monitoring and serum gastrin measurements on day 7 of three different regimens: pirenzepine 75 mg alone, vonoprazan 10 mg alone, and vonoprazan 10 mg plus pirenzepine 75 mg administered in a randomized crossover fashion.

RESULTS

Median pH 4 holding time ratios (range) achieved with pirenzepine 75 mg, vonoprazan 10 mg, and vonoprazan 10 mg plus pirenzepine 75 mg were 6.9% (2.4-32.8%), 88.4% (54.6-100%), and 84.2% (40.3-100%), respectively. Respective serum gastrin levels were 79 (75-210) pg/ml, 310 (110-870) pg/ml, and 170 (140-930) pg/ml. In cases with hypergastrinemia (gastrin ≥ 200 pg/ml) induced by vonoprazan 10 mg alone, concomitant treatment with pirenzepine significantly reduced serum gastrin levels from 370 to 180 pg/ml (P = 0.028).

CONCLUSION

Although pirenzepine does not enhance acid inhibition, it does improve hypergastrinemia induced by vonoprazan to some extent.

Effect of a proton-pump inhibitor on intestinal microbiota in patients taking low-dose aspirin

BACKGROUND AND AIM

Low-dose aspirin (LDA) administration prevents cerebral infarction and myocardial infarction, but many studies found an association with mucosal injury. Proton-pump inhibitors (PPIs) can prevent gastric and duodenal mucosal damage, but they may exacerbate small-intestinal mucosal injury by altering the microbiota. We aimed to assess the effect of PPIs on the intestinal flora of LDA users.

METHODS

Thirty-two recruited patients, who received LDA (100 mg/day) but did not take PPIs, were divided into 15 patients additionally receiving esomeprazole (20 mg/day) and 17 patients additionally receiving vonoprazan (10 mg/day). On days 0, 30, 90, and 180, the microbiota of each patient was examined by terminal restriction fragment length polymorphism analysis, and the serum gastrin, hemoglobin, and hematocrit levels were measured.

RESULTS

Additional PPI administration increased the proportion of Lactobacillales in the microbiota of LDA users. This trend was more prevalent in the vonoprazan group (p < 0.0001) than in the esomeprazole group (p = 0.0024). The Lactobacillales proportion was positively correlated with the gastrin level (r = 0.5354). No significant hemoglobin or hematocrit level reduction was observed in subjects receiving LDA with additional PPI.

CONCLUSIONS

Additional PPI administration increased the Lactobacillales proportion in the microbiota of LDA users. The positive correlation between the gastrin level and the proportion of Lactobacillales suggested that the change in the intestinal flora was associated with the degree of suppression of gastric acid secretion. Additional oral PPI did not significantly promote anemia, but the risk of causing PPI-induced small-intestinal mucosal injury in LDA users should be considered.

Long-term vonoprazan therapy is effective for controlling symptomatic proton pump inhibitor-resistant gastroesophageal reflux disease

Vonoprazan, a novel potassium-competitive acid blocker, results in greater inhibition of gastric acid secretion than proton pump inhibitors (PPI). The aim of this study was to assess the long-term outcomes of patients with PPI-resistant gastroesophageal reflux disease (GERD) treated with vonoprazan. The medical records of patients with symptomatic GERD treated with vonoprazan for 1 year were retrospectively reviewed. Changes in abdominal symptoms were assessed using the Izumo scale, a self-reported questionnaire which is useful in evaluating the symptoms of GERD, epigastric pain, postprandial distress, constipation and diarrhea, and is commonly used in routine clinical practice. A total of 30 patients were included and stratified into a non-erosive (n=22) and erosive group (n=8). At baseline, postprandial distress symptoms were significantly greater in the non-erosive group compared with the erosive group (P=0.013). Even with vonoprazan therapy, symptoms of GERD in the non-erosive group were refractory compared with the erosive group, and required additional treatment in a larger proportion of patients (45 vs. 13%). GERD symptoms in the non-erosive group significantly improved from baseline and remained better after 1 year of vonoprazan therapy, similar to the erosive group. In addition, vonoprazan improved epigastric pain and postprandial distress symptoms in the non-erosive group, and 1 year of vonoprazan therapy did not aggravate constipation or diarrhea. In conclusion, 1 year of vonoprazan therapy improves GERD symptoms in patients with PPI-resistant GERD.

Supragastric belching in Japan: lower prevalence and relevance for management of gastroesophageal reflux disease compared to United Kingdom

BACKGROUND

Supragastric belching (SGB) may play a role in the pathophysiology of proton pump inhibitors (PPIs)-refractoriness in gastroesophageal reflux disease (GERD). SGB may be present in up to 40% of reflux symptoms in PPI-refractory GERD. Most reports on SGB have come from Western countries, and little is known about the prevalence and relevance of SGB in Asian refractory GERD patients. This study aimed at comparing the role of SGB in GERD patients in Japan and the UK.

METHODS

We re-analyzed impedance-pH monitoring tracings from patients who were referred to tertiary centers in Japan and the UK due to PPI-refractory reflux symptoms. The prevalence of excessive SGB and the impact of SGB on reflux symptoms were compared between the two countries.

RESULTS

Impedance-pH tracings from124 Japanese and 83 British patients were re-analyzed. Japanese patients were significantly younger and had smaller body mass index than the British (P < 0.001). Japanese patients had significantly lower prevalence of excessive SGB (18.5%) than the UK (36.1%) irrespective of reflux phenotype (P = 0.006). Logistic regression analysis showed that the geographical/cultural difference was the only factor associated with the different prevalence of SGB (odds ratio; 2.91, 95% CI 1.09-7.73, P = 0.032). SGB were related to typical reflux symptoms very rarely in Japan [0% (0-4.9)] compared to the UK [35% (0-54.1)] (P = 0.071).

CONCLUSIONS

The prevalence of SGB and their impact on reflux symptoms is significantly lower in Japan compared to the UK. The difference is not related to reflux parameters but might come from ethnic/cultural factors to be further characterized.